The father of two children who were stabbed to death has been released without charge after questioning.
The 39-year-old and the children's mother, 35, were arrested after the five-year-old boy and girl, aged four, were found with fatal injuries.
The couple's six-month-old daughter, who was also stabbed, has undergone surgery and is critically ill.
The children were found at the family home in Carshalton, south London, on Friday night.
The Metropolitan Police said the man would face no further action in relation to the children's deaths.
Mother in hospital
But he has been bailed to return to a police station on another matter.
The children's mother remains under arrest and is in hospital where she is being treated for minor injuries.
The names of the children and their parents have not been released by police.
The dead children have yet to be formally identified and police want to ensure other relatives have been informed.
The house where the children were found remains taped off as the investigation continues.
The injured boy and girl died within 15 minutes of each other shortly after being taken to hospital.
The baby girl is said by police to be in a critical but stable condition in hospital, following her operation.
BBC NEWS | England | London | Stabbed children's father freed